////////////////////////////////////////////////////////////////////////////
//	Module 		: sight_manager_target.cpp
//	Created 	: 27.12.2003
//  Modified 	: 08.04.2008
//	Author		: Dmitriy Iassenev
//	Description : sight manager target functions
////////////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "sight_manager.h"
#include "ai/stalker/ai_stalker.h"
#include "stalker_movement_manager_smart_cover.h"
#include "level_graph.h"
#include "ai_space.h"
#include "ai/stalker/ai_stalker_space.h"
#include "detail_path_manager.h"

void CSightManager::SetPointLookAngles(const Fvector &tPosition, float &yaw, float &pitch, Fvector const& look_position, const CGameObject *object)
{
	Fvector						my_position = look_position;
	Fvector						target = tPosition;
	if (!aim_target(my_position, target, object)) {
		target					= tPosition;
		my_position				= look_position;
	}

	target.sub					(my_position);
	target.getHP				(yaw,pitch);

	VERIFY						(_valid(yaw));
	yaw							*= -1;

	VERIFY						(_valid(pitch));
	pitch						*= -1;
}

bool CSightManager::aim_target	(Fvector &my_position, Fvector &aim_target, const CGameObject *object) const
{
	if (!object)
		return					(false);

	if (m_object->aim_bone_id().size()) {
		m_object->aim_target	(aim_target, object);
		return					(true);
	}

	if (!object->use_center_to_aim())
		return					(false);

	m_object->Center			(my_position);
#if 1
	//. hack is here, just because our actor model is animated with 20cm shift
	m_object->XFORM().transform_tiny	(
		my_position,
		Fvector().set(
			.2f,
			my_position.y - m_object->Position().y,
			0.f
		)
	);
#else
	const CEntityAlive			*entity_alive = smart_cast<const CEntityAlive*>(object);
	if (!entity_alive || entity_alive->g_Alive()) {
		aim_target.x			= m_object->Position().x;
		aim_target.z			= m_object->Position().z;
	}
#endif

	return						(true);
}

void CSightManager::SetFirePointLookAngles(const Fvector &tPosition, float &yaw, float &pitch, Fvector const& look_position, const CGameObject *object)
{
	Fvector						my_position = look_position;
	Fvector						target = tPosition;
	if (!aim_target(my_position, target, object)) {
		target					= tPosition;
		my_position				= look_position;
	}

	target.sub					(my_position);
	if (fis_zero(target.square_magnitude()))
		target.set				(0.f,0.f,1.f);

	target.getHP				(yaw,pitch);
	VERIFY						(_valid(yaw));
	VERIFY						(_valid(pitch));
	yaw							*= -1;
	pitch						*= -1;
}

void CSightManager::SetDirectionLook()
{
//	MonsterSpace::SBoneRotation				orientation = object().movement().m_head, body_orientation = object().movement().body_orientation();
//	orientation.target						= orientation.current;
//	body_orientation.target					= body_orientation.current;
	if (GetDirectionAngles(object().movement().m_head.target.yaw,object().movement().m_head.target.pitch)) {
		object().movement().m_head.target.yaw	*= -1;
		object().movement().m_head.target.pitch	*= 0;//-1;
	}
	else
		object().movement().m_head.target	= object().movement().m_head.current;
	object().movement().m_body.target		= object().movement().m_head.target;
}

void CSightManager::SetLessCoverLook(const CLevelGraph::CVertex *tpNode, bool bDifferenceLook)
{
	SetDirectionLook	();

	if (m_object->movement().detail().path().empty())
		return;

	SetLessCoverLook	(tpNode, MAX_HEAD_TURN_ANGLE, bDifferenceLook);
}

void CSightManager::SetLessCoverLook(const CLevelGraph::CVertex *tpNode, float fMaxHeadTurnAngle, bool bDifferenceLook)
{
	float					fAngleOfView, range, fMaxSquare = -1.f, fBestAngle = object().movement().m_head.target.yaw;
	m_object->update_range_fov(range,fAngleOfView,m_object->eye_range,m_object->eye_fov);
	fAngleOfView			= (fAngleOfView/180.f*PI)/2.f;

	CLevelGraph::CVertex	*tpNextNode = 0;
	u32						node_id;
	bool bOk = false;
	if (bDifferenceLook && !m_object->movement().detail().path().empty() && (m_object->movement().detail().path().size() - 1 > m_object->movement().detail().curr_travel_point_index())) {
		CLevelGraph::const_iterator	i, e;
		ai().level_graph().begin(tpNode,i,e);
		for ( ; i != e; ++i) {
			node_id			= ai().level_graph().value(tpNode,i);
			if (!ai().level_graph().valid_vertex_id(node_id))
				continue;
			tpNextNode = ai().level_graph().vertex(node_id);
			if (ai().level_graph().inside(tpNextNode,m_object->movement().detail().path()[m_object->movement().detail().curr_travel_point_index() + 1].position)) {
				bOk = true;
				break;
			}
		}
	}

	if (!bDifferenceLook || !bOk) 
		for (float fIncrement = object().movement().m_body.target.yaw - fMaxHeadTurnAngle; fIncrement <= object().movement().m_body.target.yaw + fMaxHeadTurnAngle; fIncrement += fMaxHeadTurnAngle/18.f) {
			float fSquare = ai().level_graph().compute_high_square(-fIncrement,fAngleOfView,tpNode);
			if (fSquare > fMaxSquare) {
				fMaxSquare = fSquare;
				fBestAngle = fIncrement;
			}
		}
	else {
		float fMaxSquareSingle = -1.f, fSingleIncrement = object().movement().m_head.target.yaw;
		for (float fIncrement = object().movement().m_body.target.yaw - fMaxHeadTurnAngle; fIncrement <= object().movement().m_body.target.yaw + fMaxHeadTurnAngle; fIncrement += 2*fMaxHeadTurnAngle/60.f) {
			float fSquare0 = ai().level_graph().compute_high_square(-fIncrement,fAngleOfView,tpNode);
			float fSquare1 = ai().level_graph().compute_high_square(-fIncrement,fAngleOfView,tpNextNode);
			if	(
					(fSquare1 - fSquare0 > fMaxSquare) || 
					(
						fsimilar(fSquare1 - fSquare0,fMaxSquare,EPS_L) && 
						(_abs(fIncrement - object().movement().m_body.target.yaw) < _abs(fBestAngle - object().movement().m_body.target.yaw))
					)
				)
			{
				fMaxSquare = fSquare1 - fSquare0;
				fBestAngle = fIncrement;
			}

			if (fSquare0 > fMaxSquareSingle) {
				fMaxSquareSingle = fSquare0;
				fSingleIncrement = fIncrement;
			}
		}
		if (_sqrt(fMaxSquare) < 0*PI_DIV_6)
			fBestAngle = fSingleIncrement;
	}

	object().movement().m_head.target.yaw = angle_normalize_signed(fBestAngle);
	object().movement().m_head.target.pitch = 0;
	VERIFY					(_valid(object().movement().m_head.target.yaw));
}


bool CSightManager::GetDirectionAngles				(float &yaw, float &pitch)
{
	if (!object().movement().path().empty() && (m_object->movement().detail().curr_travel_point_index() + 1 < m_object->movement().detail().path().size())) {
		Fvector				t;
		t.sub					(
			object().movement().path()[m_object->movement().detail().curr_travel_point_index() + 1].position,
			object().movement().path()[m_object->movement().detail().curr_travel_point_index()].position
		);
		t.getHP				(yaw,pitch);
		return				(true);
	}
	return					(GetDirectionAnglesByPrevPositions(yaw,pitch));
};

bool CSightManager::GetDirectionAnglesByPrevPositions(float &yaw, float &pitch)
{
	Fvector					tDirection;
	int						i = m_object->ps_Size	();

	if (i < 2) 
		return				(false);

	CObject::SavedPosition	tPreviousPosition = m_object->ps_Element(i - 2), tCurrentPosition = m_object->ps_Element(i - 1);
	VERIFY					(_valid(tPreviousPosition.vPosition));
	VERIFY					(_valid(tCurrentPosition.vPosition));
	tDirection.sub			(tCurrentPosition.vPosition,tPreviousPosition.vPosition);
	if (tDirection.magnitude() < EPS_L)	return(false);
	tDirection.getHP		(yaw,pitch);
	VERIFY					(_valid(yaw));
	VERIFY					(_valid(pitch));

	return					(true);
}